Figure 4: Proliferation rate of sheep cardiac progenitor cells when compared with similar clones isolated from humans. The proliferation rate of neonatal sheep and neonatal human cardiovascular progenitor clones was indicated by the OD 450 absorbance using a proliferation assay kit. Sheep CPC had a lower proliferation rate when compared with human CPC (0.35 ± 0.01 vs. 0.51 ± 0.01, P=0.017), suggesting that CPC from sheep proliferate more slowly than comparable clones isolated from age-matched humans.